This invention relates to a subassembly of printed circuit boards for use in an electronic device, such as an electronic wristwatch, and more particularly to a printed circuit board subassembly useful in an electronic device utilizing an electro-optic sensor.
A common construction in an electronic wristwatch utilizes a printed circuit board, on which are disposed various circuit elements connected in circuit relationship with contact pads which, are connected in turn with other circuit elements or with leads to other necessary electrical components, such as pushbuttons, power supplies, liquid crystal displays and the like. In small electronic devices, such as wristwatches, very little space is available and, as integrated circuits get larger and more complex, the printed circuit board (PCB) becomes more crowded.
The addition of an electro-optic sensor and its associated circuit elements to an electronic wristwatch, such as the Timex.RTM. Data Link.TM. watch manufactured by applicant's assignee, results in too many circuit elements to conveniently be carried on a single PCB. It is convenient to group the electro-optic circuit elements on a second PCB for separate handling and testing. The problem of placement of a second PCB in the electronic wristwatch then becomes difficult due to the fact that the LCD display which is connected to the normal PCB, and the electro-optic sensor which is connected to the other PCB must both be exposed at the top of the wristwatch facing the user.
Accordingly one object of the present invention is to provide an improved PCB subassembly for an electronic device.
Another object of the invention is to provide an improved PCB subassembly for an electronic wristwatch having an electro-optic sensor.